A father convicted of killing almost half of his family has joined his son in filing an intention to appeal.

Mohammad Shafia, 58, his wife Tooba Yahya, 42, and their son Hamed, 21, were convicted Sunday of four counts each of first-degree murder.

They were found guilty of killing Shafia's daughters Zainab, 19, Sahar, 17, and Geeti, 13, and his first wife in a polygamous marriage, Rona Amir Mohammad, 52.

The judge described the killings as being motivated by the Shafias' "twisted concept of honour."

The Shafia patriarch has now filed an inmate notice of appeal, the first step in the process toward filing a full appeal at a later date, and his son filed one earlier this week.

They both list the same three grounds for appeal: that the judge admitted hearsay from their dead family members, that he admitted evidence from an "honour killings" expert and they also raise an issue with his charge to the jury.